First of all, I recently joined the forums, read about this game on some gaming website which I can't remember right now, and it got me hooked up.
A few thing I've noticed (although I haven't read the whole suggestions....yet) is that apparently there is no concern for some sort of raw metal resource, I mean, gold food stone and wood is okay, but unless all weapons are made of gold and stone, or conjured by magical means, there should be some kind of mining system. Another thing that came up is, that I've seen no mention of a profession system kind of like in Hinterland, if your units can levelup and they're all kind of unique, shouldn't they give something in return to society? During war, everyone joins in battle, but outside of it? Archers should be hunters, or trackers, there should be armorsmiths, blacksmiths, and etc etc
I know it would add a big layer of micromanagement, but it would also add a layer of depth rarely seen in rts games. Maybe I'm just asking for something that's not plausible , but maybe someone out there agrees with me.
Another thing that I think could help, would be a military academy, let's say you have veteran units, and you have rookies. The vets know a thing or two, so they should be able to teach the new units, and that way they could acquire new skills and such.
Suggestions? I'm open for them

For first part of your post, here is magic =), so blame it for that.
For second part. In this game you will always be in war so that (farmer in peace and soldier in war) is not needed =P. Beside that i like your idea.
There will be also training grounds (to lvl troops outside of battle) so that covers your suggestion of veterans teaching newcomers.

I'd like to see traps in the game. In the stronghold games you could put pitch on the field in front of your castle walls and set it on fire with flaming arrows to kill your attackers. There were also things like rolling logs over the castle walls to kill the guys climbing ladders and people below.

I think that having traps would add an interesting tactical element, and each race could have some race only traps. They could be used to further differentiate the different races and how they fight.